1. Field of the Invention
The present invention relates to multimedia devices, and more particularly, to computer-connected video and audio devices.
2. Description of Background Art
Computer connected video cameras are known, including Internet connected video cameras. Conventional Internet-connected video cameras are World Wide Web (or xe2x80x9cWebxe2x80x9d) based video cameras. Conventional web video camera systems are configured to perform web cam functions. A web cam system includes a video transmitter and a video viewer. The video transmitter generates a video clip or video stream. The video transmitter continuously obtains (or xe2x80x9cgrabsxe2x80x9d) in rapid succession video frames and uploads (e.g., posts) them to a web server where they are saved in a file. The conventional web video camera system also includes a video viewer. The video viewer downloads the saved video frame from the file on the web server. A conventional video viewer will download saved video frames from the file on the web server at an interval as fixed by a web browser of the video viewer.
Conventional web cam systems have numerous drawbacks. One problem with conventional web cam systems are continuous uploading of video frames to the web server despite no video viewers downloading the video frames for prolonged periods of time, if at all. Another problem is that conventional web cam systems continuously upload video frames despite no change occurring between the content captured within one video frame to another video frame. In turn, the video viewer that downloads the video frames downloads the same content over and over. In each described instance, it is clear that conventional web video cameras conventional web cam systems waste resources such as network bandwidth, computing system resources, and electrical power to transmit video frames that have no viewership or no change in content from one video frame to another.
Web video cameras may also be used in conventional peer-to-peer video conferencing systems. In conventional peer-to-peer video conferencing systems, two computers, each with a web video camera, are in direct communication with each other over a direct network connection. Each web video camera transmits video frames across the direct network connection from its computer to the other computer. A significant problem with conventional peer-to-peer video systems includes the need for a large quantity of bandwidth to transmit the video frames back and forth between the two computers. Moreover, similar to conventional web cam systems, conventional peer-to-peer systems continuously transmit video frames even when there is no change occurring in the content of the transmitted video frames. Yet another problem with this approach is that bandwidth capacity may be severely limited by the network connection (e.g., a 56 kbps modem connection) so that unnecessary transmission of video frames results in lost video frames and/or degraded video transmission. Thus, similar to conventional web video cameras used in conventional web cam systems, conventional web video cameras used in conventional peer-to-peer video systems also unnecessarily diminish limited network bandwidth and unnecessarily draw and use computing system and electrical power resources to transmit its video frames.
Therefore, there is a need for a video camera system and method for transmitting video frames for receipt by a computer without unnecessarily drawing upon and using network, computing, and power resources on a continual basis.
The present invention includes a video and audio processing system for transmission of one or more video frames and/or one or more audio frames across a network. For ease of discussion, the system will be described with regard to a video processing system and the principles described herein are applicable to audio processing so that discussion of the video processing system is understood to include audio processing.
The video processing system includes a video input mechanism, a motion detection mechanism, and a web cam mechanism. The video input mechanism is configured to receive a first video frame and a second video frame. In one embodiment one of the video frames, e.g., the first video frame, serves as a reference video frame.
The motion detection mechanism is configured to compare the first video frame with the second video frame. The motion detection mechanism is also configured to generate a motion-detected signal if the comparison of the two frames deviates from (e.g., exceeds or falls below) a threshold value. The threshold value may be any variable that allows for a comparison between the first video frame and the second video frame. The threshold value may be set at a pre-determined value. The web cam mechanism is configured to transmit the non-reference video frame, e.g., the second video frame, to the network if the web cam mechanism receives the motion detection signal from the motion detection mechanism.
The present invention also includes a method for processing one or more video frames for transmission across a network. The method includes receiving a video frame from a video input. The video input may be, for example, a video camera that records real-time video or a video source that stores video frames such as a storage device or a memory. The method compares the received video frame with a reference video frame. The reference video frame may be stored or obtained in advance of the received video frame.
The method determines if a comparison of the received video frame and the reference video frame deviates from the threshold value. This comparison may be done to determine if there is motion detected between the received video frame and the reference video frame. The threshold value may be used to determine whether the motion detected, if any, is sufficient enough to warrant transmitting the received video frame. If the comparison deviates from the threshold value the video frame is transmitted and if it does not deviate from the threshold value the video frame is discarded. If there is deviation from the threshold value and the received video frame is transmitted, the received video frame may become the new reference frame.
The video processing system and method in accordance with the present invention provides a number of benefits and advantages. For example, the video processing system and method beneficially saves computing system resources by processing, saving, and transmitting video frames that meet a particular threshold requirement that indicates that there was sufficient (or alternatively, insufficient) motion detected from one video to another video frame.
In addition, the video processing system and method beneficially reduces network bandwidth consumption because only selected video frames, which show movement from one video frame to another, are transmitted over the network. Further, the present invention may be advantageously applied to web cam systems that transmit images from a user system to a web cam server or to peer-to-peer user systems that allow direct connections.
Yet another advantage of the present invention is that it provides flexibility to setting parameters in the form of one or more threshold values so that frames may be updated and transmitted or frames may be dropped depending on whether there is a deviation from the threshold value. This deviation may include exceeding the threshold value or falling short of the threshold value. This flexibility beneficially allows for custom configuring of a system to maximize usage of both system and network resources based on bandwidth availability.
The features and advantages described in the specification are not all inclusive and, in particular, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the drawings, specification, and claims. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes, and may not have been selected to delineate or circumscribe the inventive subject matter.